Effect of Bed Bug (Hemiptera: Cimicidae) Aldehydes on Efficacy of Fungal Biopesticides.

The use of the entomopathogenic fungus Beauveria bassiana (Bals. - Criv.) Vuill. (Hypocreales: Cordycipitaceae) has been recently incorporated in the management of bed bugs, Cimex lectularius L. (Hemiptera: Cimicidae). Bed bugs produce a set of aldehydes that are known to affect the growth of some fungi. Considering that bed bugs or their exuviae release these aldehydes, it was suspected that the bed bugs' aggregation sites would contain an increased level of the bed bug aldehydes. The current study examined if elevated levels of the bed bug aldehydes in the microhabitats would impact the efficacy of B. bassiana. Following a brief exposure to the residues of commercial products containing B. bassiana, the treated bed bugs were kept in a vial with or without a natural or artificial blend of bed bug aldehydes (i.e., exuviae or synthetic compounds). For a B. bassiana product that is not currently registered for bed bugs control, the presence of aldehydes significantly reduced 15-d mortality (61-62%) compared to the no aldehydes control (97.7%). However, when tested with a B. bassiana formulation designed for bed bug control, the aldehydes only caused delayed mortality for the treated bed bugs. When tested in culture, the growth rate of B. bassiana on a medium was significantly reduced when the bed bug aldehydes were provided in the headspace. Implications on practical bed bug management using fungal biopesticides are discussed.

Wash-off potential of pyrethroids after use of total release fogger products.

Pyrethroids are frequently detected in urban wastewater. Even though treatment facilities remove most pyrethroids (> 90 %) in wastewater, residual concentrations can exceed thresholds that are acutely toxic to sensitive aquatic species. Total release foggers (also known as "bug bombs") are widely used by the general public for insect control. It was hypothesized that these products serve as a source of pyrethroids entering the urban wastewater through the deposition of the active ingredients on various surfaces and subsequent transfer from the contaminated surfaces to the waste stream through cleaning activities. Based on experiments conducted in an enclosure, we found that substantial amounts of a pyrethroid (i.e., cypermethrin) were deposited on various surfaces after a total release fogger use. A series of experiments simulating scenarios that would be representative of common residential cleaning activities indicated that the pyrethroid could be transferred from the contaminated surfaces to other adsorptive materials via physical contact (with or without water as a solvent). The pyrethroid was readily extracted from the adsorptive materials (cotton fabric and filter paper) when water was used as a solvent. Adding a small amount of detergent to the water significantly increased the extraction efficiency compared to water alone. These results indicate that insecticides used in total release foggers can contribute to insecticide loading into the wastewater treatment system via several possible routes, such as contact with or cleaning of exposed surfaces and washing contaminated clothing after their use within a structure.

Ontogenesis of Aldehyde Pheromones in Two Synanthropic Bed Bug Species (Heteroptera: Cimicidae).

Bed bugs produce volatile aldehydes that have alarm and aggregation functions. Using two synanthropic bed bug species, Cimex lectularius L. and C. hemipterus (Fabricius), developmental changes were examined for (E)-2-hexenal, 4-oxo-(E)-2-hexenal, (E)-2-octenal, and 4-oxo-(E)-2-octenal, the four most abundant aldehydes shared between the two species. Quantitative analyses of the aldehydes in the nymphal exuviae indicated that the aldehydes' ratio remained similar throughout nymphal development. In general, (E)-2-octenal was most abundant, and (E)-2-hexenal and 4-oxo-(E)-2-octenal were least abundant. The fourth aldehyde, 4-oxo-(E)-2-hexenal, was present in intermediate quantities. The quantities and percent abundances of the aldehydes in nymphal exuviae and the adults were significantly different between C. lectularius and C. hemipterus. The ratio between (E)-2-hexenal and (E)-2-octenal was determined in adult male and female bed bugs of each species. Adult C. hemipterus had a higher proportion of (E)-2-hexenal than C. lectularius, while no sex differences were found. This work provides the first systematic quantification of four aldehydes [(E)-2-hexenal, 4-oxo-(E)-2-hexenal, (E)-2-octenal and 4-oxo-(E)-2-octenal] for all five of the nymphal stages for both C. lectularius and C. hemipterus.

Infection control in field hospitals after a natural disaster: lessons learned after the 2010 earthquake in Haiti.

After the January 12, 2010, earthquake in Haiti, Project Medishare and the University of Miami organized, built, and staffed a 200-bed field hospital (the University of Miami Hospital in Haiti [UMHH]) on the outskirts of Port-au-Prince. We describe the operational challenges of providing a safe environment at the UMHH. Furthermore, we compared how these issues were addressed at this ad hoc hospital with how they were addressed at the field hospital of the Israel Defense Force, a fully deployable hospital with an organization fine-tuned as a result of prior disaster situations, also in Haiti.

Changing epidemiology of bacterial meningitis.

Immunization against the most common meningeal pathogens is the leading factor associated with decreased incidence of bacterial meningitis in countries where routine vaccination is available. This is most dramatically illustrated by the reduction in the incidence of Haemophilus influenzae type b meningitis. The incidence of bacterial meningitis has decreased by 55% since the introduction of the H. influenzae type b conjugate vaccine in 1990. H. influenzae occurred primarily in children younger than 5 years of age, and so the median age of patients with bacterial meningitis has now increased to 39 years of age in the United States, and the leading pathogen is currently Streptococcus pneumoniae. Three other control measures (ie, universal screening and antibiotic prophylaxis of pregnant women for Group B streptococci and the implementation and availability of the S. pneumoniae and Neisseria meningitidis conjugate vaccines) have likely further decreased the incidence of these meningeal pathogens. Lastly, the worldwide emergence of multidrug-resistant pneumococci has complicated the empiric therapy of bacterial meningitis.